None.
Not Applicable.
This invention relates generally to towing attachments mounted on vehicles. It is especially well adapted to be employed with a tractor with a three point hitch, alternatively to provide a fifth wheel hitch or a gooseneck hitch. It has particular, but not exclusive, application to a Category 3 tractor.
A wide array of loads, and many configurations and styles of load carriers, such as trailers and flat-beds are pulled by tractors with a three point hitch. Such tractors have the capacity to pull many loads over rough terrain, but are not intended to pull such heavy loads as a heavily loaded trailer such as the type pulled over the road by eighteen wheelers, but for pulling fifth wheel trailers such as farmers use on small type trucks. A three point hitch comprises two hydraulically operated arms spaced horizontally from one another in one plane, extending from the rear of the tractor, and a third pivoted arm, generally equidistant from the two arms and above the plane of the two arms; also extending from the rear of the tractor and oriented so that the three arms form three points of a triangle. In the device described, the third arm is threaded at one end and connected at that end by a yoke to the tractor and by a pintle at the other end to the attachment of this invention. Making the third arm manually adjustable is conventional, and forms no part of this invention. conventionally the three point hitch is attached directly or through a frame connected to the three arms, to a load carrier that is to be pulled by the tractor.
There are many occasions when it is desired to move a load carrier equipped with a gooseneck or a fifth wheel hitch receiver. A gooseneck hitch is a hitch in which a ball is received in a socket carried by the load carrier, the load carrier""s weight then being counterbalanced by the hitch and its own contact with the ground.
A fifth wheel hitch has on the load carrier a downwardly depending post, often with a spherical terminus, extending from a flat bearing surface. The prime mover has a plate with a hole in it to receive the post, the plate serving as a load bearing surface complementary to that of the load carrier. In the fifth wheel hitch, the hole into which the post extends usually takes the form of a notch in the rearwardly facing edge of the prime mover plate, and jaws, defining between them the xe2x80x9cholexe2x80x9d, which are opened when the post is put into position, and closed and locked in position after the post has been properly positioned. The plate""s generally smooth surface faces upwards, and the rearward portion is angled downward to provide a ramp. The bearing surface of the load carrier rests against this plate, which is well greased.
As recited in U.S. Pat. No. 4,340,240, normally a tractor three point hitch is capable of engagement with but one arrangement of implement attachment points, and none has been adapted to handle both a gooseneck and a fifth wheel type of the kind described above. The gooseneck and fifth wheel types are often associated with quite different vehicles. For instance, it is common for a flat-bed pickup truck to have a gooseneck attachment directly over the rear differential of the truck. It is common for a semi-trailer rig to incorporate a fifth wheel hitch.
The present invention provides a tractor attachment connected to a standard three point hitch which is adapted to provide a hitch for load carriers heretofore considered not compatible with a three point hitch. The attachment may readily manually be converted to a gooseneck hitch, or to a fifth-wheel hitch.